*{
    margin: 0;
    padding: 0;
}
.header{
    width: 100%;
    height: 45px;
    background: red;
}
.header .logo{
    float: left;
    margin-left: 20px;
    opacity: 0.5;
}
.header .logo:hover{
    opacity: 1;
}
.header .logo a{
    display: inline-block;
    width: 122px;
    height: 37px;
    background: url("../images/logo2.png") no-repeat 0 0;
}
.header .register{
    float: right;
    line-height: 45px;
}
.header .register li{
    list-style: none;
    float: left;
    margin-right: 20px;
    color: #ffffff;
    opacity: 0.5;
}
.header .register li:hover{
    opacity: 1;
}
.content{
    width: 100%;
    height: 560px;/*教程是460*/
    background: blue;
}
.content .content_in{
    width: 1200px;
    height: 100%;
    background: deeppink;
    margin: 0 auto;
}
.content_in .content_left{
    float: left;
    width: 800px;
    height: 100%;
    background: pink;
}
.content_left .content_toolbar{
    width: 100%;
    height: 40px;
    background: #000;
}
.content_toolbar span{
    display: inline-block;
    width: 122px;
    height: 100%;
    line-height: 40px;
    text-align: center;
    border: 1px solid #ffffff;
    box-sizing: border-box;
    border-radius:5px;
    color: #ffffff;
    opacity: 0.5;
}
.content_toolbar span i{
    display: inline-block;
    width: 18px;
    height: 18px;
    background: url("../images/css_sprites.png") no-repeat 0 0;
    margin-right: 10px;
    vertical-align: -5px;
}
.content_toolbar span:hover {
    opacity: 1;
}
.content_toolbar span:nth-child(1) i{
    background-position: -10px -46px;
}
.content_toolbar span:nth-child(2) i{
    background-position:-46px -46px ;
}
.content_toolbar span:nth-child(3) i{
    background-position: -82px -10px;
}
.content_toolbar span:nth-child(4) i{
    background-position:-46px -10px ;
}
.content_toolbar span:nth-child(5) i{
    background-position:-10px -10px;
}
.content_left .content_list{
    width: 100%;
    height: 520px;/*教程是420*/
    background: purple;
}
.content_list li{
    list-style: none;
    width: 100%;
    height: 50px;
    background:orange;
    opacity: 0.5;
    border-bottom: 1px solid rgba(255,255,255,0.5);
    box-sizing: border-box;
}
.content_list li div{
    float: left;
    color: #ffffff;
    line-height: 50px;/*行高*/
}
.content_list .list_check{
    width: 50px;
    height: 100%;
    background: black;
    text-align: center;
}
.content_list .list_check i{
    display: inline-block;
    width: 14px;
    height: 14px;
    border: 1px solid #fff;
    margin: 14px;
}
.content_list .list_number{
    width: 20px;
    height: 100%;
    background: green;
}
.content_list .list_name{
    width: 50%;
    height: 100%;
    background: #CCCCCC;
}
.list_name .list_menu{
    margin-top: 15px;
    float: right;
    margin-right: 20px;
    display: none;

}
.list_menu a{
    display: inline-block;
    width: 36px;
    height: 36px;
    background: url("../images/css_sprites.png") no-repeat 0 0;
    opacity: 0.5;
}
.list_menu a:hover{
    opacity: 1;
}
.list_menu a:nth-child(1){
    background-position: -10px -46px;
}
.list_menu a:nth-child(2){
    background-position: -46px -46px ;
}
.list_menu a:nth-child(3){
    background-position: -82px -10px;
}
.list_menu a:nth-child(4){
    background-position: -46px -10px ;
}

.content_list .list_singer{
    width: 20%;
    height: 100%;
    background: pink;
}
.content_list .list_time a{
    display: inline-block;
    width: 36px;
    height: 36px;
    background: url("../images/css_sprites.png") no-repeat -10px -10px;
    float: left;
    margin-top: 5px;
    display: none;
    opacity: 0.5;
}
.content_list .list_time a:hover{
    opacity: 1;
}
.content_in .content_right{
    float: right;
    width: 400px;
    height: 100%;
    background: #CCC;
}
.footer{
    width: 100%;
    height: 60px;
    background: green;
    position: absolute;
    left: 0;
    bottom: 0;
}
.footer .footer_in{
    width: 1200px;
    height: 100%;
    background: plum;
    margin: 0 auto;
}
